Sol-Ark 8/12/15k with Tigo TS4-A-O?

[dlSOLAR]

Hopefully simple question for this crowd. I'm a long time solar owner, but everything up to now has been installed by others. (Primarily Solaredge equipment).

We moved, and I'm heading down the DIY path. The expensive stuff is all purchased and in hand, now working out the fine details:

* Sol-Ark 15k
* Nx48V LIFO4 Batteries
* 8-12 450W panels, W facing, mostly flat roof.

Some healthy panel shading by the house early in the morning, intending to run TS4-A-O's to compensate. Trying to understand the TIGO eco system and how it ties to the Sol-Ark.

Q1: I assume I also need a Tigo CCA to communicate to the TS4's, then be cabled RS-485 to the Sol-Ark so it can talk to the TS4's, trigger rapid shutdown, etc?
Q2: Any other questions I should be asking?

Thanks!

 

[Balthazar-B]

I don't know whether Tigo optimizers can be integrated cleanly with Sol-Ark inverters, but you may be interested to know that in Sol-Ark's most recent press release regarding CEC certification for the 15K, they mentioned that among their upcoming products will be optimizers. I can only think they will be optimized for their own ecosystem -- as their imminent microinverters will be -- and it's possible details will be made available at the RE+ conference in Anaheim next month. Might be worth waiting to see what they'll do, what they'll cost, and when they'll be GA.

 

[dlSOLAR]

Thanks @Balthazar-B - appreciate the reply - will be watching for news.

From my reading, it looks while the optimizers will run "stand alone" - the CCA is the only thing that will "read" the optimizers AND send the keepalives which will trigger the rapid shutdown once removed.

Parts incoming - will update as we go.

 

[400bird]

Some healthy panel shading by the house early in the morning, intending to run TS4-A-O's to compensate. Trying to understand the TIGO eco system and how it ties to the Sol-Ark.

There was some discussion recently and someone linked to this article. I'm not sure how applicable, because the author is in Australia and it was written 8 months ago. In short, you might need to buy their gateway thing and update your optimizers for them to function properly.

Tigo Optimiser Recall?

Tigo optimisers seemed like a good idea at the time. In the past, I’ve spruiked Tigo as an affordable shade solution. But my recent Tigo testing has uncovered two major issues that render Tigo…

www.mcelectrical.com.au

Q1: I assume I also need a Tigo CCA to communicate to the TS4's, then be cabled RS-485 to the Sol-Ark so it can talk to the TS4's, trigger rapid shutdown, etc?

Does it offer benefits to connect the inverter? The inverter doesn't need to shut down the PV, a fire crew does. Shut down should involve a large well labeled and obvious switch.

 

[surfsidebill]

I have a 8kW Solark 12k with one Tigo CCA, one TAP and 20 TS4-A-O's mounted on each of 20 Canadian Solar 440w panels. The system has only been working for a few days, but seems to be working well. It's producing about 40kWh on a day of full sun.

My understanding of the way the Tigo Rapid Shutdown works is that, when the system is working normally, the CCA sends a keep-alive to Tigo's Tigo Access Point (TAP) mounted on the array. This keep-alive is transmitted by a local short-range RF signal to each of the TS4-A-O's. As long as that keep alive is there, the system functions normally. Without the signal, the panels outputs are "off".

After speaking with Sol-Ark tech support, I concluded there is really no integration between Tigo TS4-A-O and SA (see below). My solution was for my critical loads panel to provide power to the CCA. Whenever the Rapid Shutdown button is hit, the SA shuts down, removing power from the CCA and thus removing the keep-alive to the TAP and the TS4-A-O's. It seems like a kludge, but it works.

(The SA install manual shows a diagram of a magnetically linked Tigo transmitter sending over the solar PV wire to the panels with TS4-A's. There is also a vague mention of the fact that the SA will work with the TS4-A-O, but no diagram of how to wire it. After many emails back and forth between SA tech support and Tigo tech support, it became clear that the diagram in the manual ONLY applies the TS4-A's and NOT to the TS4-A-O's. In fact, the missing information was that the CCA MUST be connected by hard wire RS-485 (or a CAT cable) to the TAP. In our case, the CCA had to be in the basement by the critical loads panel and the TAP has to be located close to the panels on the roof.)

I selected the SA12k for its flexibility and great specs. I started with it in pass-through mode without panels and ran it several months while we sorted out the communication between SA and Tigo. Once we get the CCA-TAP problem figured out, we hooked everything up and it worked without a hitch. I will add batteries next.

I cannot say whether the TS4-A-O's are degrading the system or not. This post is mostly to clear up the questions about how the SA integrates with the Tigo system.

 

[uncle_mike]

I have a 8kW Solark 12k with one Tigo CCA, one TAP and 20 TS4-A-O's mounted on each of 20 Canadian Solar 440w panels. The system has only been working for a few days, but seems to be working well. It's producing about 40kWh on a day of full sun.

My understanding of the way the Tigo Rapid Shutdown works is that, when the system is working normally, the CCA sends a keep-alive to Tigo's Tigo Access Point (TAP) mounted on the array. This keep-alive is transmitted by a local short-range RF signal to each of the TS4-A-O's. As long as that keep alive is there, the system functions normally. Without the signal, the panels outputs are "off".

After speaking with Sol-Ark tech support, I concluded there is really no integration between Tigo TS4-A-O and SA (see below). My solution was for my critical loads panel to provide power to the CCA. Whenever the Rapid Shutdown button is hit, the SA shuts down, removing power from the CCA and thus removing the keep-alive to the TAP and the TS4-A-O's. It seems like a kludge, but it works.

(The SA install manual shows a diagram of a magnetically linked Tigo transmitter sending over the solar PV wire to the panels with TS4-A's. There is also a vague mention of the fact that the SA will work with the TS4-A-O, but no diagram of how to wire it. After many emails back and forth between SA tech support and Tigo tech support, it became clear that the diagram in the manual ONLY applies the TS4-A's and NOT to the TS4-A-O's. In fact, the missing information was that the CCA MUST be connected by hard wire RS-485 (or a CAT cable) to the TAP. In our case, the CCA had to be in the basement by the critical loads panel and the TAP has to be located close to the panels on the roof.)

I selected the SA12k for its flexibility and great specs. I started with it in pass-through mode without panels and ran it several months while we sorted out the communication between SA and Tigo. Once we get the CCA-TAP problem figured out, we hooked everything up and it worked without a hitch. I will add batteries next.

I cannot say whether the TS4-A-O's are degrading the system or not. This post is mostly to clear up the questions about how the SA integrates with the Tigo system.

Bill, this may be a dumb question: the SA has MPPT charge controllers built in and the TS4-A-O also include MPPT functionality on the module. Does this create any problem with essentially 2 independent MPPTs trying to control each PV string? Perhaps with the optimization already done on-panel, the SA has nothing left to do. Perhaps they disagree on the optimum impedence match and fight each other? I don't know how this would play out and can't find a discussion of it anywhere - it may just be a dumb question.

 

[GregTR]

I just had a Sol-Ark 15K installed with 44x440W Aptos panels in 3x2 strings (2x8,2x8,2x6) with Tigo optimizers.

I'm still waiting for the batteries but the Sol-Ark 15K is working fine as is with the optimizers. Unlike the Tigo RS units, the optimizers come "hot" so they will optimize and work straight out of the box without the CCA and the TAP being live and working. But once they're connected to the CCA and the TAP they will need signal to run going forward. The Tigo RS units come "cold" so they will not work unless they receive RF signal on the PV wires. The TAP units are daisy chained to each other and require telephone wire from the CCA to pass the signal on the wire to the TAP from where they broadcast a wireless signal to the optimizers which work in a mesh and talk to each other, propagating the signal throughout the roof.

I'm still waiting for the CCA, but I have two TAP units on the roof (I have East, South, West facing panels that are not together). I can't tell how well the optimizers work but since I have some partial shading on the East side and mismatched roof pitches I went with the optimizers. So far I'm impressed with the system, today I got 42kWh of self consumption and I could have gotten WAY more if I had a battery as I never even hit maximum production during the day except for about 30 minutes in the morning when I was charging my EV.

The bottom line is that the Sol-Ark manual specifically calls out that the CCA cannot be connected to the Sol-Ark's 12V power as it only provides 100mA and the CCA needs about 700mA. So you have to use the Tigo provided power supply which I just run off of one of the 15A circuits on my main panel. So if the breaker goes, or there is a complete AC shudown at the Sol-Ark the panels will also rapid shutdown.

But if I only lose grid power, my panels will keep operational as long as the Sol-Ark stays up and provides energy to my house. The only time I would lose everything is if the batteries died, the Sol-Ark shut down and I had no AC power as I would be unable to turn the PV on without power to the CCA so I would either need to find an alternate power source for the CCA to turn on the PV without having A/C power at the breaker panel.

I also wonder about how firefighters will know to turn off power to my panel, pulling the meter will not de-energize the house at all, it very much will stay on until the main breaker in the garage is killed, which will also initiate the rapid shutdown.

As for the multiple MPPT question, the Tigo unit is basically a buck/boost converter that will adjust the lower performing panel's voltage to match the incoming current from the other panels. So if a panel is partially shaded and it has low current, it will drop the voltage and boost the current to match the flow from the other panels. This is not an MPPT, it doesn't optimize the power output of the individual cell, it sacrifices voltage for current so the rest of the current can flow through the panel. It may work in the other direction where it might increase the voltage of the other panels to reduce their current to match the lower performing panel's. Since you can use Tigo Optimizers sparingly, meaning you don't need to have one on every panel for the optimization to work (I did buy 44 of them) this is how it has to work.

Then your inverter can still do the MPPT optimization of the string to get peak power out of them. It works really well together and poses absolutely no problems. As soon as I have my CCA, I will be able to perform panel level monitoring and see how each panel performs.

 

[uncle_mike]

I just had a Sol-Ark 15K installed with 44x440W Aptos panels in 3x2 strings (2x8,2x8,2x6) with Tigo optimizers.

As for the multiple MPPT question, the Tigo unit is basically a buck/boost converter that will adjust the lower performing panel's voltage to match the incoming current from the other panels. So if a panel is partially shaded and it has low current, it will drop the voltage and boost the current to match the flow from the other panels. This is not an MPPT, it doesn't optimize the power output of the individual cell, it sacrifices voltage for current so the rest of the current can flow through the panel. It may work in the other direction where it might increase the voltage of the other panels to reduce their current to match the lower performing panel's. Since you can use Tigo Optimizers sparingly, meaning you don't need to have one on every panel for the optimization to work (I did buy 44 of them) this is how it has to work.

Then your inverter can still do the MPPT optimization of the string to get peak power out of them. It works really well together and poses absolutely no problems. As soon as I have my CCA, I will be able to perform panel level monitoring and see how each panel performs.

Thank you for explaining the interaction between panel-level optimizers and MPPTs. I'm moving ahead with 54x MSE 345s + Tigo "O" units (6 strings of 9) + Sol-Ark 15K + 4x SOK 5.12 kWh server rack batteries. I probably shouldn't be so excited.

 

[GregTR]

You absolutely should be excited! I finally got my battery installed and today I was on free electricity all day long!

The Sol-Ark 15K is an absolute beast. You won't be disappointed!

 

[moonlight23]

I also wonder about how firefighters will know to turn off power to my panel, pulling the meter will not de-energize the house at all, it very much will stay on until the main breaker in the garage is killed, which will also initiate the rapid shutdown.

I'm also getting a Sol-Ark, and the ONLY solution I found for RSD is going with this Tigo module, CCA, and TAP system if I want to keep the PV array DC-coupled. Your detailed post has helped a lot, so thank you!

I'm no solar engineer or electrician, but I think what you might be missing is that you still need a large button for RSD outside of your house for emergency responders to access? Otherwise like you mentioned, they will not be able to know how to easily shut down the CCA to turn off the PV arrays.

From the Sol-Ark manual, it looks like you have to hook up this button to pins 11 and 12 on the sol-ark. So my question is, is this external button functionally any different than the built in "PV Disconnect" switch on the side of the sol-ark?

 

[GregTR]

I'm also getting a Sol-Ark, and the ONLY solution I found for RSD is going with this Tigo module, CCA, and TAP system if I want to keep the PC array DC-coupled. Your detailed post has helped a lot, so thank you!

I'm no solar engineer or electrician, but I think what you might be missing is that you still need a large button for RSD outside of your house for emergency responders to access? Otherwise like you mentioned, they will not be able to know how to easily shut down the CCA to turn off the PV arrays.

From the Sol-Ark manual, it looks like you have to hook up this button to pins 11 and 12 on the sol-ark. So my question is, is this external button functionally any different than the built in "PV Disconnect" switch on the side of the sol-ark?

To answer your question, no, that button would not do anything useful at all if it's wired as shown.

That button basically does nothing but cuts the 12V power on pin 15 and 16. Since the Sol-Ark manual specifically states that the Tigo CCA unit with optimizers must not use the 12V circuit of pin 15 and 16 due to its current limit of 100 mA while the CCA needs 700 mA that will not work.

So my CCA is just wired to a regular A/C breaker inside my panel which means unless the breaker is tripped the strings stay energized. That breaker will not trip on its own and even with grid power disconnected it will remain energized thanks to the Sol-Ark providing power. The key is that the CCA also has a Normally Open button input that can be wired up if you want a PV rapid shutdown button. There is no requirement for this button in NEC that I know of so you can have one but not I would certainly not put it by my AC disconnect on the side of the house. https://support.tigoenergy.com/hc/e...g-a-Manual-Latching-Push-Button-Safety-Switch

Additionally with batteries even if you flip the PV disconnect or the rapid panel shutdown the house still remains energized, you have to disconnect DC breaker from the Sol-Ark as well to lose all source of power. If you read the Sol-Ark instructions the steps involve shutting down the load breaker, PV disconnect and the unit itself before DC disconnect on the battery, you don't want to throw that breaker with 150A running through it. So if you go through all those steps your house will be de-energized and the rapid shutdown sequence would initiate due to the CCA's power being shut down via the breaker it is connected to losing power.

So I personally wouldn't worry about a rapid shutdown emergency button but I am also highly skeptical whether firefighters would have any idea about what to look for on a solar home to make sure everything is de-energized. When I used to be a certified volunteer firefighter we were trained to pull the meter when you roll up on a structure fire. That was over a decade ago and things have obviously changed a lot since then.

 

[moonlight23]

To answer your question, no, that button would not do anything useful at all if it's wired as shown.

That button basically does nothing but cuts the 12V power on pin 15 and 16. Since the Sol-Ark manual specifically states that the Tigo CCA unit with optimizers must not use the 12V circuit of pin 15 and 16 due to its current limit of 100 mA while the CCA needs 700 mA that will not work.

It's very contradictory that sol-ark would specifically reference Tigo units in the manual several times for RSD, but the DC power terminal can't actually support the CCA power requirement.

So my CCA is just wired to a regular A/C breaker inside my panel which means unless the breaker is tripped the strings stay energized. That breaker will not trip on its own and even with grid power disconnected it will remain energized thanks to the Sol-Ark providing power. The key is that the CCA also has a Normally Open button input that can be wired up if you want a PV rapid shutdown button. There is no requirement for this button in NEC that I know of so you can have one but not I would certainly not put it by my AC disconnect on the side of the house. https://support.tigoenergy.com/hc/e...g-a-Manual-Latching-Push-Button-Safety-Switch

I live in a California where everything is strict here and I'm a little worried this method won't pass inspection.

NEC 2017 Code 690.12(B)(2):
an initiation device(s) shall be located at a readily accessible location outside the building. The rapid shutdown initiation device(s) shall consist of at least one of the following:
(1) Service disconnecting means
(2) PV system disconnecting means
(3) Readily accessible switch that plainly indicates whether it is in the “off” or “on” position.

So without a big fat red button outside, the CCA wired to a breaker in the main service panel outside would still qualify, as long as it's labeled ON and OFF for PV? And hypothetically speaking, if the sol-ark was mounted outside, then the built in "PV Disconnect" on the side would qualify as the RSD button if it's labeled?

I think this guy did a great job explaining this, although he uses a different inverter:

 

[Balthazar-B]

I live in a California where everything is strict here and I'm a little worried this method won't pass inspection.

If you poke through the big 15k thread and others, you should find at least a half dozen or so Californians who have installed this inverter already. Perhaps reaching out to a few to find out how their setups were designed to pass muster with their utilities and AHJs would accelerate the planning process for you?

Given how wacky California is in terms of regulation and permitting, there should be threads devoted to our local peculiarities. In the case of the 15k specifically, maybe content added to this thread would make discussions of related best practices and lessons learned easier to find: https://diysolarforum.com/threads/solark-15k-approved-for-california.45331/.

 

[Lt.Dan]

I live in a California where everything is strict here and I'm a little worried this method won't pass inspection.

I'm in Central California, and I just installed a 12k with the Tigo CCA, TAP, and Optimizers. The Inspector approved it and there is no disconnect outside for it. Everything is in my garage. There are warning labels on my main service panel (outside), that notates there is an alternative power source in the home, and the location of that source (in the garage).

It's very contradictory that sol-ark would specifically reference Tigo units in the manual several times for RSD, but the DC power terminal can't actually support the CCA power requirement.

Tigo does make other RSD that are supported by the DC power terminal, just not the CCA. There are many more brands that also support that DC power terminal, APSmart is one of them.

 

[GregTR]

It's very contradictory that sol-ark would specifically reference Tigo units in the manual several times for RSD, but the DC power terminal can't actually support the CCA power requirement.

The manual specifically calls out the CCA not being compatible, there is no ambiguity in the manual. That 12V connection works for your basic toroid signal generator that goes over your PV lines for the rapid shutdown only solution.

NEC 2017 Code 690.12(B)(2):
an initiation device(s) shall be located at a readily accessible location outside the building. The rapid shutdown initiation device(s) shall consist of at least one of the following:
(1) Service disconnecting means
(2) PV system disconnecting means
(3) Readily accessible switch that plainly indicates whether it is in the “off” or “on” position.

So without a big fat red button outside, the CCA wired to a breaker in the main service panel outside would still qualify, as long as it's labeled ON and OFF for PV? And hypothetically speaking, if the sol-ark was mounted outside, then the built in "PV Disconnect" on the side would qualify as the RSD button if it's labeled?

I highlighted the correct parts. ;-). Not you have to have "one" not "all". So the cheapest and easiest solution is a service disconnect, which is what almost all solar installers install. This is about protecting the grid worker not the firefighter.

I think this guy did a great job explaining this, although he uses a different inverter:

That guy is actually in Texas and he chose to do a DC disconnect rather than an AC disconnect, which for his system works as it's not a hybrid inverter so no DC = no power. I even commented on another video of his with this info a few months back.

 

[Sciguy]

Just completed Sol-ark 12k with Tigo TS-A-O, TIGO CCA, and Tigo Tap. To handle turning off power to CCA for rapid shutdown, I used a 3phase 60amp disconnect on the outside of the house instead of the normal single phase 2 pole disconnect. 2poles disconnect the grid connection to the Sol-ark, and I used the 3rd pole to break the 110vac power connection to the CCA. This achieves rapid shutdown with the 1 disconnect on the outside of the house. No secondary red buttons required.

It passed code but the inspector probably didn't notice how it was connected.

I powered the CCA from a sub-panel attached to the load side of the Solark. This let me use a reasonable size circuit breaker (15amp) to power the dinky power supply for the CCA. I added a 1 amp fuse in front of the dinky CCA power supply as a safety measure.

Since the Solark can start inverting as UPS function on the load terminals when the grid is down, it let's me "dark start" everything and get the panels producing to feed the batteries when the grid is down. All while the Sol-Ark stays isolated from the grid.

 

[Sciguy]

The Tigo TS4A-O is a buck only architecture, you can google it. I've had my system working for about a month now. There is a shortcoming to lacking the boost ability when strings are paralleled.

The attached picture shows my panel wattages in the middle of the day. Strings A&B are parallel wired. Strings C&D are parallel wired. A tree is shading B5,B6,D1,D2. B1-B4 should be producing full power like row A. D3-D6 should also be producing full power. I believe what is happening is that there isn't enough voltage in string B to match string A (since Tigo doesn't have boost ability) so string B is way away from peak power in the panel IV curve. Thus 8 panels in full sun have 50% production due to 4 panels in shade :-(

The TS4-A-O optimizers just can't help when the string voltages are too far apart due to shading.

Unfortunately, I think my only solution to the lower strings getting poor production is a chain saw.

 

[Lt.Dan]

Unfortunately, I think my only solution to the lower strings getting poor production is a chain saw.

Chain saw is always the cheaper way of getting more solar output! Lol

 

[GregTR]

View attachment 115612
The Tigo TS4A-O is a buck only architecture, you can google it. I've had my system working for about a month now. There is a shortcoming to lacking the boost ability when strings are paralleled.

The attached picture shows my panel wattages in the middle of the day. Strings A&B are parallel wired. Strings C&D are parallel wired. A tree is shading B5,B6,D1,D2. B1-B4 should be producing full power like row A. D3-D6 should also be producing full power. I believe what is happening is that there isn't enough voltage in string B to match string A (since Tigo doesn't have boost ability) so string B is way away from peak power in the panel IV curve. Thus 8 panels in full sun have 50% production due to 4 panels in shade :-(

The TS4-A-O optimizers just can't help when the string voltages are too far apart due to shading.

Unfortunately, I think my only solution to the lower strings getting poor production is a chain saw.

Thanks for the info about the optimizer being "buck only". However this should not stop parallel strings still producing optimal power by reducing voltage on the full sun panels to match that of the shaded ones and increase the current on the sunny ones given that we stay within MPPT limits. My understanding was that this is precisely why you need the CCA when you have strings in parallel, so the Tigo can optimize the two strings better.

I still don't have my CCA so I have no insight into how much of an improvement I will get once the Tigo is correctly set up but I do have east and west facing panels and they should mirror each other's production. Since only the west side has shading (from a dormer, can't use the chainsaw solution) I should be able to have a pretty good comparison between the two sides. Right now shading costs me a significant amount of loss.

I guess in my scenario my only saving grace is going to be that I have 4 panels that receive dormer shade and two are on one string and the other two are on the other string, bringing string voltages closer together. Also, the two panels that get less shade are the sting where I have two panels with a lower roof angle on the other side.

I should have my CCA next week so I'll post results after that.

 

[Lt.Dan]

I just got mine up and running last week and am pleasantly surprised by it. I found out that one panel has partial shade (D11), but it doesn't slowdown the other panels. This snapshot was just a few minutes ago, and it looks like D11 being down is not affecting the rest of the parallel string D.

On a side note, I can see that C8 and C1 are underperforming a bit compared to the others. I'll keep an eye on them, and if they get worse, I can plan to swap them out.